A Latino group has published an open letter urging "all Americans" to reject certain hard-line immigration policies. Above, U.S. Border Patrol agents detain people who crossed the border from Mexico in McAllen, Texas, Aug. 7, 2015. Photo: John Moore/Getty Images

A conservative group of Latinos has denounced the immigration policies touted by several Republican presidential contenders, including current front-runner Donald Trump. The LIBRE Initiative, which describes itself as advancing "the principles and values of economic freedom to empower the U.S. Hispanic community so it can thrive and contribute to a more prosperous America," sent an open letter Wednesday urging "all Americans" to reject proposals for mass deportation and ending birthright citizenship.

In particular, Daniel Garza, the executive director of the LIBRE Initiative and author of the letter, wrote in part that proposals to end the legal right to citizenship for all children born on U.S. soil regardless of the parent's status, as well as deporting law-abiding undocumented immigrants, "are not in line with our principles and are not in the best interest of the country."

Without naming any names, the letter seemed directly aimed at Republican presidential hopefuls, led by Trump and his anti-immigration rhetoric but likely including others who have taken a hard line, such as Texas Sen. Ted Cruz, New Jersey Gov. Chris Christie, Louisiana Gov. Bobby Jindal and Wisconsin Gov. Scott Walker.

As recently as last week, Trump's stance on immigration spurred a protest following a speech he delivered in New York pledging his allegiance to the Republican Party and promising not to run as a third party candidate. In that instance, an impromptu demonstration was staged, including a man dressed in a Ku Klux Klan-style white robe toting a sign that read, "MAKE AMERICA RACIST AGAIN!"

The LIBRE Initiative is funded by the Koch brothers, the conservative billionaires who back many Republican candidates, according to NPR.